## Department of Mathematics and Statistics

#### Resources

##### Main Campus
###### University Hall

Second Floor Rm 2040
419.530.2568
419.530.4720 Fax

### Colloquia

Colloquia for the Department of Mathematics and Statistics are normally held in University Hall 4010 on Fridays at 4:00pm. Any departures from this are indicated below.

Light refreshments are served after the colloquia in 2040 University Hall.

Driving directions, parking information, and maps are available on the university website.

# 2016-2017 Colloquia

What follows is a list of speakers, talk titles and abstracts for the current academic year. Abstracts for the talks are also posted in the hallways around the departmental offices.

## Fall Semester

December 2, 2016

Timothy Clos (University of Toledo)

Compactness of Hankel Operators with Continuous Symbols

Abstract: Hankel operators are an area of research in operator theory. I will begin this talk by surveying some background material concerning Hankel operators and compactness of operators. I will then give some previous results on compactness of Hankel operators on the Bergman spaces of domains in $\mathbb{C}^n$ for $n\ge 1$. I will also outline the proof of our main result, which concerns compactness of Hankel operators with symbols which are continuous up to the closure of convex Reinhardt domains in $\mathbb{C}^2$.

This is a joint work with Sönmez Şahutoğlu.

November 18, 2016

Evolutionarily Stable Strategies in the Evolution of Condition Dispersal

Abstract: Dispersal, which refers to the movement of an organism between two successive areas impacting survival and reproduction, is one of the most studied concepts in ecology and evolutionary biology. How do organisms adopt their dispersal patterns? Is there an "optimal", or evolutionarily stable, dispersal strategy that emerges from the underlying ecology? In this talk, we consider a reaction-diffusion model of two competing species for the evolution of conditional dispersal in a spatially varying but temporally constant environment. Two species are different only in their dispersal strategies, which are a combination of random dispersal and biased movement upward along the resource gradient. In the absence of biased movement or advection, A. Hastings (1983) showed that dispersal is selected against in spatially varying environments. When there is a small amount of biased movement or advection, we show that there is a positive random dispersal rate that is both locally evolutionarily stable and convergent stable. Our analysis of the model suggests that a balanced combination of random and biased movement might be a better habitat selection strategy for populations.

This is joint work with Y. Lou of Ohio State University.

October 7, 2016

Vani Cheruvu (University of Toledo)

Numerical methods, grids in atmospheric and oceanic sciences

High-order numerical methods offer the promise of accurately capturing many physical processes and have been shown to efficiently scale to large number of processors. There is a considerable effort in using high-order methods to solve partial differential equations that model physical phenomena in atmospheric and oceanic sciences. In this talk, I would present three different high-order methods and discuss their advantages and disadvantages. These methods are compared by applying to a PDE. Several issues are involved when these methods are applied to a PDE on a sphere for instance, suitability of a grid. I will conclude the talk with two suitable grids on a sphere.

# Colloquia for Previous Years

#### ... and More

Generated on: 2016-11-29 01:58 UTC.